Computer Failure Recovery Scheme

[spectrum]

Let me set the scene of a hypothetical scenario and please share your knowledge regarding the recovery scheme. Owning a back-up computer is not an option for this exercise.

The scenario:
Diving in Bonaire
Recreational maximum depths, 40-100 feet
Exclusively EAN 32
Do not consider PPO2
3-5 dives per day
55-80 minutes per dive
Dives were very multi-level
Profiles have not been archived
BT & MAx depths were not recorded, they were lost in the computer.
Diver was solo, no other diver with a "close" dive history
2 week visit
For this exercise forget about visiting the salt farm, donkeys or national park, we want to maximize diving.

Computer fails during a dive that surfaces at 7PM on day 3

Shot in the dark Recovery Plan

Rent a nitrox dive computer
Set it for air
Day 4: Resume normal diving pattern with EAN32 at 7AM the next day on the theory that the air penalty will offset the remaining residual nitrogen after a 12 hour SI.

Day 5: Set computer for EAN32 and carry on with the dive trip SOP. The theory here being that after diving EAN32 to air limits any nitrogen absorption from the first 3 days has been over shadowed by using air calculations on day 4 while diving EAN32.

I know this is totally anecdotal but the logic seems to make sense. Is there a devil in the details such as the behavior of certain tissue compartments?

Have fun,
Pete

 

[texdiveguy]

"(Anecdotal)-- is an informal account of evidence in the form of an anecdote or hearsay. The term is often used in contrast to scientific evidence, such as evidence-based medicine, which are types of formal accounts. Anecdotal evidence is often unscientific because it cannot be investigated using the scientific method. Misuse of anecdotal evidence is a logical fallacy and is sometimes informally referred to as the "person who" fallacy ("I know a person who..."; "I know of a case where..." etc. Compare with hasty generalization). Anecdotal evidence is not necessarily typical; statistical evidence can more accurately determine how typical something is."

 

[in_cavediver]

Depending on the algorthim used, you may be 'clean' after 12 hours anyway.

Personally, I'd take the new computer, dive it as normal (ean 32) and do what I always do when multi-day diving - spend more time at my safety stops and don't push any limits.

 

[spectrum]

"(Anecdotal)-- is an informal account of evidence in the form of an anecdote or hearsay. The term is often used in contrast to scientific evidence, such as evidence-based medicine, which are types of formal accounts. Anecdotal evidence is often unscientific because it cannot be investigated using the scientific method. Misuse of anecdotal evidence is a logical fallacy and is sometimes informally referred to as the "person who" fallacy ("I know a person who..."; "I know of a case where..." etc. Compare with hasty generalization). Anecdotal evidence is not necessarily typical; statistical evidence can more accurately determine how typical something is."

Swell! But does our hero (or heroine) get bent?

Pete

 

[miketsp]

Swell! But does our hero (or heroine) get bent?

Pete

After 12 hours on my tables & computer the OP would be clean for diving purposes.
Just rent a Nitrox computer and set according to the mix in use.

Just don't abuse & ride the profile - basic advice anyway for multiday multidive diving.

 

[amascuba]

Or just have enough competence in your knowledge about decompression theory that a computer failure doesn't faze you and you continue your diving vacation as planned with a rented computer using it as a bottom timer and ignoring the calculations it presents you.

And listen to your body before, during, and after dives. Your body knows all and tells all.

 

[do it easy]

And listen to your body before, during, and after dives. Your body knows all and tells all.

What kinds of things do you look out for? I'm of the school of thought that your body will only tell you when you haven't done enough deco.

 

[chrispete]

Theoretically? I'd go have a beer and sit the night dive out. I'd restart diving the next morning using a 36% mix on a Nitrox computer set to 21% and limit my depth to a conservative but fun 40 feet or so. After a day of that I'd resume normal schedule with the same computer...

 

[texdiveguy]

..I am still working on this word... anecdotal!!

 

[TwoBitTxn]

DAN has been preaching about not doing this type of dive trip for awhile now. That is the 5 day multi dive vacation. There is gowing evidence showing people getting hurt at the end of these trips.

There is also growing evidence that after multiple days of diving with multiple dives per day tissues are not clean and clear after 12 hours. It may be more like 24 or more. Even as a hypothetical, my recommendation to this individual would be to take a day off, go sight seeing, and resume diving with the rented computer.

TwoBit